Included conda update in docker setup file.

Signed-off-by: Daniel Scheffler <danschef@gfz-potsdam.de>

tests/CI_docker/context/sensormapgeo_ci.docker

@@ -4,9 +4,10 @@ FROM gms_base_centos:0.3
 COPY *.yml /root/
 
 # update the ci_env environment (that already contains all packages installed via 'docker_pyenvs' repo)
-# NOTE: we update Python to avoid version incompatibilities
+# NOTE: We update conda and Python to avoid version incompatibilities.
 RUN /bin/bash -i -c "\
     source /root/miniconda3/bin/activate ; \
     source activate ci_env; \
+    conda update -n base -c defaults conda ; \
     conda update -c conda-forge python ; \
     conda env update -n ci_env -f /root/environment_sensormapgeo.yml"